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General information

  • Name: TPD
  • Full name: N,N'-Bis(3-methylphenyl)-N,N'-bis(phenyl)-benzidine
  • CAS number: 65181-78-4
  • Chemical formula: C38H32N2
  • Molecular weight: 516.67 g/mol
  • Absorption: λmax = 352 nm in THF
  • Photoluminescence: λmax = 398 nm in THF
  • HOMO/LUMO: HOMO = 5.5 eV, LUMO = 2.3 eV
  • Synonyms: N,N′-Bis(3-methylphenyl)-N,N′-diphenylbenzidine, N,N'-Diphenyl-N,N'-di(m-tolyl)benzidine, 4,4'-Bis[N-phenyl-N-(m-tolyl)amino]biphenyl
  • Classification: Light-emitting diodes, Organic light-emitting diodes, Hole injection layer materials (HIL), Hole transport layer materials (HTL), Host materials
  • Purity: Sublimed: >99%
  • Melting point: 175 - 177 °C
  • Appearance: White powder/crystals

TPD: Leading Material for OLED Efficiency

TPD, formally N,N’-Bis(3-methylphenyl)-N,N’-bis(phenyl)-benzidine, with CAS number 65181-78-4, stands at the forefront of materials science for organic light-emitting diodes (OLEDs). This compound, with a molecular formula of C38H32N2, is integral to the fabrication of high-performance OLEDs, serving as a crucial component in hole injection layer (HIL) and hole transport layer (HTL) materials, as well as a versatile host material. Boasting a sublimation purity of over 99%, and optimal HOMO and LUMO levels, TPD is indispensable for developing OLED devices that combine high efficiency with enhanced durability.

The Molecular Structure and Properties of TPD

TPD’s molecular architecture, characterized by the bis(phenyl)benzidine backbone substituted with methyl groups, is ingeniously designed to facilitate efficient hole transport within OLED devices. This configuration promotes enhanced charge carrier mobility, essential for the stability and efficacy of OLED displays. The energy levels of TPD, with a HOMO of 5.5 eV and a LUMO of 2.3 eV, enable effective energy transfer and electron mobility, contributing to devices that offer improved brightness and energy efficiency.

Key Features of TPD

  • Optimal Charge Transport: TPD is renowned for its superior hole transport capabilities, a crucial attribute that significantly reduces energy dissipation within OLED devices, thereby elevating their operational efficacy. This exceptional ability to facilitate smooth and efficient charge carrier mobility is instrumental in enhancing the electroluminescence efficiency of OLEDs. By optimizing the interface between the emissive layer and the anode, TPD ensures a reduction in turn-on voltages and an increase in the overall luminous efficiency, contributing to the sustainability and energy conservation of OLED technology.
  • Versatility in OLED Applications: The molecular design of TPD, characterized by its chemical and electronic flexibility, renders it highly versatile across a spectrum of OLED applications. Its utility extends beyond traditional hole injection and transport layers, serving also as an effective host material for a range of phosphorescent dopants. This adaptability enhances the compatibility of TPD with various emissive materials, promoting innovative solutions in the development of OLED displays and lighting systems. By facilitating a broad range of device architectures, TPD plays a pivotal role in the exploration and realization of advanced OLED functionalities, driving forward the boundaries of what is possible in organic electronics.
  • Superior Purity and Performance: With a sublimation purity exceeding 99%, TPD stands out for its exceptional quality, directly translating to OLED devices that boast unparalleled performance and reliability. This high level of purity minimizes the presence of impurities that could otherwise lead to quenching effects or operational instability, ensuring that OLEDs maintain their color purity and brightness over extended periods. The rigorous control of material purity underpins the development of high-efficiency OLEDs that are capable of operating at lower voltages, further enhancing the energy efficiency and lifespan of these devices. TPD’s role as a material of choice for cutting-edge OLED development is solidified by its contribution to superior device architecture and performance standards.

The Role of TPD in Advanced OLEDs

TPD plays a transformative role in the realm of OLED technology, facilitating the development of displays that not only dazzle with aesthetic brilliance but are also characterized by environmental efficiency. As a critical component in both HIL and HTL materials, TPD significantly enhances light emission efficiency and device durability. This contribution is key to driving OLED technology forward, enabling the production of displays that excel in visual appeal, energy efficiency, and longevity.


TPD epitomizes Noctiluca’s commitment to excellence in the field of OLED material science, offering innovative solutions that address the evolving needs of the OLED industry. Our expertise in supplying high-quality TPD, combined with comprehensive services in chemical manufacturing and research, cements Noctiluca’s position as a leader in the development of state-of-the-art OLED technologies. By championing the use of superior materials like TPD, Noctiluca is at the vanguard of propelling display technology into the future, ensuring our partners achieve unprecedented success in device performance, visual quality, and ecological sustainability.

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